Method and apparatus for quenching filaments



P 1969 R. CONSTANTAKIS ET AL 3,440,685

METHOD AND APPARATUS FOR QUENCHING FILAMENTS Filed Dec, 28, 1966 INVENTORS ROBERTO CONSTANTAKIS JAMES J. HUDGENS AGENT United States Patent (9 3,440,685 METHOD AND APPARATUS FOR QUENCHING FILAMENTS Roberto Constantakis and James J. Hudgens, Pensacola, -Fla., assignors to Monsanto Company, St. Louis, Mo.,

a corporation of Delaware Filed Dec. 28, 1966, Scr. No. 605,366 Int. Cl. D01d 11/00 US. Cl. 18-8 1 Claim ABSTRACT OF THE DISCLOSURE An apparatus and method for conditioning freshly spun synthetic filaments by passing the filaments through a controlled refrigerated zone of relatively still air.

Background of the invention Melt spun thermoplastic filaments, such as nylon and polyester filaments, are conventionally cooled or quenched by passing them through a stream of forced air. In forced air quench systems, particularly where forced air is directed perpendicularly to the passage of filaments through the quench chamber, turbulent air conditions are often encountered causing undesirable disturbance of linear passage of the filaments through the quench chamber. Turbulent air conditions result in filament vibration, excessive bowing and arcing of filaments and nonuniform filament-to-filament quenching. The disclosed method and apparatus I for quenching filaments provides advantages over the prior art in that filaments are quenched in a relativelystill, refrigerated atmosphere minimizing undesirable bowing, fluttering and vibration of filaments and providing a more uniform conditioning thereof.

Summary of the invention According to the invention, freshly spun thermoplastic filaments are cooled by passing the filaments through a controlled refrigerated air zone defined by an elongated enclosure having a spinneret positioned 'at its upper end and a convergence guide at its lower end. Refrigeration means surround the inner walls of the enclosure leaving a central passage for the travel of filaments therethrough.

In method, the refrigeration means is controlled to maintain the air in the quench zone at a predetermined cool temperature by radiative exchange of thermal energy while filaments are extruded and passed through the relatively still air quench zone.

Brief description of the drawing In the drawing a single figure of the novel thermally cooled quench unit is shown in perspective.

Description of a preferred embodiment Referring to the drawing, the refrigerated quench unit comprises an enclosure or chimney 1, as commonly referred to in the art defining an elongated, confined quench chamber 2. A circular chimney 1 configuration is shown, but it will be understood that other chimney shapes may be used.

Chimney 1 comprises a pair of hingedly connected half shells 3 and 4. Shell 3 is pivotal and serves as a door while the other shell 4 is fixedly mounted. An evaporator coil 5 is mounted on the inside of and close to the walls of shells 3 and 4. Evaporator coil 5 is connected to a refrigeration unit 6 of conventional structure. The upper end of shells 3 and 4 are adapted to mate closely around a spinneret 7 connected to a source of polymer flow.

The lower ends of shells 3 and 4 have slotted end walls 8 and 9, respectively. When shells 3 and 4 are closed, the interfaces of end walls 8 and 9 mate to form a single end wall with an opening therethrou-gh. A convergence guide 10 is mounted on end walls 8 and 9 overlapping the opening provided by the latter.

The sectioned end walls and convergence guide are illustrated embodiments. Other constructions may be used, as for example the end wall and convergence may be of integral construction. Evaporator coil 5 has flexible connections to permit pivotal opening of shell 3. An optional expedient is a Plexiglas window 11 for observing the process when shells 3 and 4 are closed. With shells 3 and 4 closed, except for the opening in the bottom end wall, chamber 2 is contained or confined. An unobstructed passage through the center of chamber 2 from the spinneret to the convergence guide is provided.

In operation, pivotal shell 3 is locked and chamber 2 is refrigerated to a predetermined temperature controlled by refrigeration unit 6. An operator then opens shell 3 and laces filaments extruding from spinneret 7, as with an aspirator or sucker gun, centrally through the quench chamber 2 and through convergence guide 10 and then onto a yarn take-up means such as a driven bobbin, not shown. Shell 3 is then closed. Thermoplastic filaments were quench according to the following example.

Example I A refrigeration quench unit of the type described above was manufactured and placed in operation. The unit was approximately 42 inches long. The inside chamber 2 temperature was maintained at approximately C. measured about 10 inches from the face of spinneret 7. A bundle of 26 nylon filaments of 280 total denier was spun from spinneret 7 and laced through the unit in the manner described above. The filaments were successfully quench and taken up on a bobbin.

To make a comparative test, thermoplastic filaments were quench according to the following examples.

Example II A quench chimney of conventional design having sidewalls, a foraminous backwall, and an open front was prepared adjacent to the refrigerated quench chimney referred to in Example I. A spinneret identical to the spinneret used in the refrigerated chimney having 26 capillaries was employed at the upper end of the conventional unit. The spinneret was connected to the same source of polymer as was the spinneret of the refrigerated chimney and the polymer was delivered to both spinnerets under like controlled conditions. A cross flow of air at a velocity of approximately 80 feet per minute and of a temperature of approximately 80 C. was directed through the established foraminous wall into the chimney. A bundle of 26 nylon filaments of 280 total denier was spun through the conventional chimney, quenched, converged and taken up on a bobbin.

Example III The bobbins of yarn produced by Examples I and II were then processed on the same drawtwister in like manner with both yarns being drawn 371% and given a Z- twist of 0.41 per inch. The total denier of the drawtwisted yarn of Example I was 39.7 while that of Example 11 was 40.6. Thirty-five (35) pounds of yarn quenched according to Example I and 28 pounds of yarn quenched according to Example II was processed on the drawtwister.

In drawtwisting both types of yarns it was found that a six-fold improvement in drawtwist performance was realized in processing the yarn quench in the refrigerated chimney according to Example I. The drawtwist performance being the measurement of breaks occurring per chamber and exiting therefrom through the opposite pounds of yarn processed. The drawtwist performance of opening, the yarn quenched according to Example I was 0.17 while refrigeration means including an evaporator coil that quenched according to Example II was 1.07. mounted in said enclosure.

It will be understood that variations and modifications 5 of the embodiments of the yarn quench apparatus and References Cited method described are expected to be covered Within the UNITED STATES PATENTS spirit of the invention and that limitations are only contemplated within the scope of the following claims.

1. A filament quench apparatus comprising: 10 enclosure means defining an elongated quench chamber with openings at opposite ends thereof WILLIAM J. STEPHENSON, Primary Examiner. spinneret means for extruding filaments into said quench chamber through one of said openings, said filaments passing longitudinally through said quench 15 264 176, 237, 348

2,367,493 1/1945 Fordyce et al. 2,940,122 6/1960 Collat. 

